The invention relates generally to merchandise order picking systems and, more particularly, to merchandise order picking systems of the type including a rack having a plurality of shelves and a work table movable along the rack. A person walks along the face of the rack for selectively removing merchandise therefrom and placing same on the movable work table.
Merchandise order picking systems of the type described have been in use for many years. One of the earliest systems may be described as being similar to the manner of shopping in a modern supermarket where a freely wheeled cart is moved along the floor past shelves containing different merchandise. However, a freely wheeled cart or work table will not travel along closely adjacent the shelves, and is rather difficult to manipulate to insure that it will not block aisle passages. Therefore, another known system includes upper and lower rails adjacent the top and bottom of the merchandise rack. One or more elongated upright supports are supported on the rails by wheels or rollers. One or more panels are cantilevered on the upright supports to form a movable work table. A system of this type is quite expensive to install because it requires both upper and lower horizontal rails. In addition, the upright supports and the work table must be of very heavy construction to withstand the stresses encountered due to the cantilevered construction. A substantial number of supporting and guiding rollers is required for the upper and lower ends of the upright supports in order to provide free movement of the work table along the rails, while also taking the large loads.